GC Inlet Liner

What is the GC Inlet Liner?

A GC inlet liner is a glass tube inside the injection port where the sample vaporises. Its geometry and deactivation affect peak shape and column protection, and correct liner geometry protects the column.

Overview

The liner is a deactivated glass tube, commonly 4 mm outside diameter and 78.5 mm long, in split, splitless, straight, tapered or baffled designs, with or without glass wool. It sits inside the heated injection port, where the sample is vaporised and mixed with carrier gas before entering the column. Glass wool retains involatile residues so they do not reach the column, and baffles or tapers improve mixing and reduce discrimination against high-boiling components. Deactivation, often by silanisation, prevents active analytes from adsorbing and tailing. The liner must be replaced periodically because residue build-up causes peak tailing, carry-over and loss of response. Choice depends on the injection mode, the sample cleanliness and whether the analytes are active or thermally labile.

How does it work?

Chromatography consumables work by providing a clean, inert flow path and by protecting the analytical column from particulates, involatile residues and reactive analytes. In gas chromatography, the inlet liner holds the injected sample while it vaporises, and its geometry, packing and deactivation affect peak shape and whether involatile material reaches the column; a septum seals the inlet and must reseal after many injections without bleeding siloxanes. In liquid chromatography, frits at the column ends retain the packing while allowing liquid through, and the pore size must be fine enough not to let particles pass but coarse enough to avoid high pressure. PEEK tubing and fittings replace stainless steel where metal interaction or salt corrosion matters. Guard cartridges add a small length of similar packing before the analytical column so contaminants are retained there and the expensive column lasts longer.

What are the key features?

• Deactivated glass tube
• 4 mm OD, 78.5 mm length
• Split, splitless, tapered or baffled
• Glass wool or empty
• Silanised deactivation
• Periodic replacement for residue control

What are the technical specifications?

A typical gc inlet liner configuration offers material of Deactivated borosilicate glass, outer diameter of 4 mm, length of 78.5 mm, design of Split, splitless, tapered, baffled, glass wool of Optional and deactivation of Silanised. Values are indicative of the product class; the exact figures for each configuration are confirmed on the quotation and the calibration documents supplied with the instrument.

Which applications is it used for?

The GC Inlet Liner is used in split and splitless GC injection, residual solvent testing, trace environmental analysis and flavour and fragrance work. Across the wider Chromatography Consumables class, laboratories also deploy it for gas chromatography injection, liquid chromatography and UHPLC and ion chromatography.

Which standards and certifications apply?

Relevant standards and methods include USP <621> (chromatography), USP <467> (residual solvents), USP <788> (particulate matter in injections), ISO/IEC 17025 (testing and calibration laboratories) and USP <1058> (analytical instrument qualification). Certification candidates for this model are CE and ISO 9001 manufacturing; each is to be confirmed for the specific configuration before shipment, and certificates are supplied only where they have been issued.

Replace liners, septa and guard cartridges on a schedule based on injection count and sample cleanliness, not only when performance visibly degrades, since contamination develops gradually. Keep a log of replacements and the symptoms that prompted them, such as peak tailing, carry-over or pressure rise. Check the exact part number and dimensions, because a wrong ferrule or liner can leak, leak air into the detector or damage the injection port. Handle frits and liners with clean tools to avoid contamination, and never reuse a liner from one method in another without cleaning and inspection. Confirm that PEEK fittings are used within their pressure and temperature range, and store parts in their packaging. Verify that new lots do not introduce ghost peaks before routine use.

How do I select the right GC Inlet Liner?

Choose the liner design for the injection mode and the glass wool for dirty samples, with deactivation for active analytes. RFQ: instrument model, injection mode, sample type, temperature and analyte activity. Provide instrument model and analyte activity.

How does it compare with other Chromatography Consumables variants?

Match each consumable to the instrument, the method and the analytes. For GC, choose a liner with a geometry and packing suited to the injection mode, split or splitless, and deactivated for active analytes; choose a septum with the right temperature limit and bleed characteristics for the analyte concentrations and run length. For LC, choose frits of the correct porosity and material, and PEEK or titanium fittings for ion analysis and high-salt mobile phases. Add a guard cartridge that matches the analytical column chemistry, and replace it before contamination reaches the column. Confirm the dimensions, thread types and pressures before ordering, because fittings and frits are not interchangeable between systems. Where trace analysis is done, request lot information and test blanks to confirm low background.